Steam generator



Jan. 18, 1955 G. A. REHM STEAM CENERATOR Filed April 1949 United States Patent 2599761 p srEAM-GENERmoR Gustav A. Rehm, Springfield, Ill., assignor to Springfield Boiler Company, Springfield, lll., a Corporation of Illinois My invention relates to an improvement in steam generators and has for one purpose to provide a generator or furnace of relatively large size and high rate.

Another purpose is to provide a steam generator n which, in a structure of large size and high rate, it is possible to keep the furnace temperatures below the fusing point of the slag or impurties in the fuel in order to prevent undue slagging or coating of the boiler tubes.

Another purpose is to provide an improved steam reheater arrangement for such a furnace.

Another purpose is to provide an improved steam superheater arrangement for such a furnace.

Another purpose is to provide a furnace of the above type in which a reheater and a superheater are arranged in a manner and location to increase the efliciency of the complete generator.

Other purposes will appear from time to time in the course of the specification and claims.

The invention is illustrated more or less diagrammatically in the accompanying drawing wherein I illustrate a vertical section of the invention.

Like parts are indicated by like symbols throughout the specification and drawing.

Referring to the drawing I illustrate a form in which, in a straight tube boiler, the superheater and the reheater are generally vertically arranged, and at one side of the initial combustion chamber. It will be understood, however, that the superheater and reheater tubes may be employed in the bent tube boiler designs, and may be arranged at any angle from horizontal to vertical, and may be supported in any desired manner.

Referr'ng specifically to the drawing and to the reheater and superheater portions, the reheater tubes are illustrated at 100, with associated headers 101 and 102. The superheater tubes are indicated at 105, with connecting headers 106 and 107. 108 generally indicates the combustion chamber, which need not be described in detail. 31 indicates any suitable steam drum, and 31a is any suitable lower drum, the two drums being connected by any suitable tubes 31b, shown as generally vertical, with oflset end portions for connection with the drums 31 and 31a. It will be noted that, at one side, the combustion chamber 108 is closed by a partition 110 having an upper edge portion defining an opening or passage 109 through which the heated products of combustion may flow. The superheater and reheater tubes, as will be clear from the drawing, have connected portions on each side of the partition 110, the superheater and reheater tubes being associated and extending in general parellelism. A downwardly extending flue passage is dened between the partition 110 and the partition 111. A third partition 112 extends downwardly from the drum 31, and between the tubes 31b, and the above described reheater and superheater tubes.

It will be noted that transversely extending bottom par titons 1110 and 112a define a passage which may be closed by a closure 114. The closure 114 is shown as in closed position. When in such position all 'the heated products of combustion are constrained to flow downwardly between the partitions 110 and 111 and then transversely below the partition 111a and upwardly about or beyond the end of the passage closed by the closure 114. At the first pass, above the drum 310, the heated products of combustion flow through and about the lower ends of the tubes 31b. The heated gases may be constrained to a tortuous path through the tubes 3112 by the 2,699,761 ?atented Jan. 18, 1955 `'staggered 'transversepartitions115, 116 and .1'17. `11:18

indicates any suitable' flue outlet. 'It will" be understood that when the opening 114 is opened, part of the heated gases may bypass the superheater and reheater tube portions extending downwardly between the partitions and 111, and may flow outwardly through the outlet between the transverse partitions 111a and 112a.

Although the diagrammatic illustration shows a straight tube boiler design, the princple of furnace division and placing of superheater and reheater tubes applies to the bent tube boiler design equally as well, except that superheater and reheater tubes may be arranged at any angle from horizontal to vertical, or pendant type, tube loop arrangement.

I illustrate a structure which is applicable to both straight and bent tube boilers. It is applicable to dual or multiple chamber furnaces. That is to say, whereas I illustrate only one combustion chamber, I could, under certain circumstances, employ more than one.

It will be understood that I may burn diiferent fuels, but since the details of the boilers as such do not form part of the present invention, I illustrate, merely diagrammatically, nozzles 9a.

It will be understood that the above-described disposition of the superheater and the reheater may be applied both to straight tube and to bent tube boilers, to single combustion chamber boilers, and to multiple combustion Changer boilers, whether the individual chambers are equal or unequal in size, and to difierentially fired multiple chamber boilers.

As a matter of fact, since reheaters are generally applied where pressure of over one thousand pounds is employed, my invention may be more universally applied to bent tube boilers than to straight tube boilers. However, straight tube boilers are used at temperatures sutficiently high to render my arrangement of superheater and reheater advantageous.

I claim:

1. In a boiler and a furnace therefor, :a first partition, a front wall, parallel side walls and a roof defining a combustion chamber, said partition constituting the rear wall of said combustion chamber, the upper edge of said partition being spaced from the roof of said combustion chamber to define therewith an exit passage for the gases of said combustion chamber, a second partition spaced from said first partition and defining therewith a convection passage, means forming a floor for said latter passage, the lower edge of said second partition being spaced from said floor of said convecton passage to define therewith an exit for said convection passage, a first group of superheater tubes positioned in an upper portion of said combustion chamber adjacent said combustion chamber exit passage, a second group of superheater tubes positioned in said convection passage, the tubes of the first and second superheater groups being connected through said combustion chamber exit passage above the upper edge of said first partition, a first group of reheater tubes positioned in an upper portion of said combustion chamber adjacent said combustion chamber exit passage, a second group of reheater tubes positioned in said convection passage, the tubes of said first and second reheater groups being connected through said combustion chamber exit passage above the upper edge of said first partition, portions of the reheater tubes of said first reheater group being interlaced with portions of the superheater tubes of said first superheater group, portions of the reheater tubes of said second reheater group being interlaced with portions of the superheater tubes of said second superheater group, said interlaced portions of said first and second groups extending above and below the upper edge of said first partition.

2. The structure of claim 1 characterized by and including a third partition positioned between said first and second partitions, said third partition having an upper edge lying in substantially the same horizontal plane with said first partition, said third partition being spaced from said first partition and enclosing therebetween the lower portions of said second reheater and superheater groups, said third partition being spaced from said second partition and defining therewith a substantially unobstructed by-pass flue positioned to fiermit some of the gases flowng through said convectiox passage to by-pass said lower portons of said second rehaterand superheater groups,

said thrd partition includingan end portion through'said convecton passage exit.

xtending r Referenca Cited in the file of this patent UNITED STATES PATENTS Kemnal L Oct. 18, 1927 Oct. 24, 1933 Mar. 27, 1934 I FF 

